The present invention relates to window coverings, such as curtains and shades. One embodiment of the invention comprises a motorized window covering apparatus comprising a detachable power supply unit.
Window coverings, such as curtains and shades, are known in the art and are used to provide privacy, to limit the amount of light that can pass through a window and into a room or building, and to decorate rooms and provide aesthetic appearances. Roller shades and cellular shades are types of window coverings that comprise material that rolls up, or compresses onto itself. Generally, they are easy to install, are available in many colors and opacities, and are easy to maintain over their life. Also known in the art are motorized shades, which comprise a motor that raises and lowers the shade. This provides added convenience to the user, who can raise or lower the shade to their preference, without manually handling the shades. Such motorized shades can include switches or remote controls.
Motorized shades are generally difficult and costly to install, especially when directly connected to household power as an electrician or other expert or professional is often required for installation. Motorized shades powered by batteries or plug-in adapters from household outlets do not require such professional expertise for installation, and are therefore generally less complex and less expensive to install. Current powered shade systems, however, suffer from disadvantages, such as the following:
Only small size batteries with limited energy capacity fit into the minimal cross-sectional area between the valance and headrail system for motorized shades, because they utilize many of the same parts (brackets, shade material, head rail and valance) as non-motorized shades to reduce the significantly higher cost for motorization. Or the power supply (especially a group of common cell batteries) is positioned outside the headrail or valance, but still utilize small size batteries to minimize adverse aesthetics as they look conspicuous and unnatural.
Systems that minimize cross-sectional area and volume by utilizing a small sized power supply (such as common AA cell sized batteries) compromise cycle life compared to larger diameter batteries (such as common C or D cell sized batteries). For example, while typical D cell size batteries have more than five times larger cross-sectional area compared to typical AA cell size batteries, they have approximately eight times more energy capacity for significantly longer cycle life for motorized shades.
Installation of whole systems (designed to fit together prior to installation) can be heavy and awkward to install, often at unstable positions many feet above the floor. Individual parts that install separately to form the system at the final location are easier to handle, because individual pieces are lighter in weight and less bulky.
All the above disadvantages increase the difficulty of installation and/or detract from the cycle life expectations and/or aesthetics of the motorized shade. Therefore, a need exists in the field for motorized shade systems that retain pleasing aesthetics with significantly longer cycle life. A further need exists to utilize a larger capacity power supply that significantly increases cycle life, again without being located external to the system and compromising aesthetics. Another need exists for simplified installation, whereby system parts are installed in pieces or modules to lessen weight and awkward handling.